Multistage machine tool



y 1969 E. FAYMONVILLE 3,452,582

MULTISTAGE MACHINE TOOL Filed Jan. 5, 1967 7 Sheet o; 3

July 1, 1969 E. FAYMONVILLE MULTISTAGE MACHINE TOOL Sheet Filed Jan. 5,1967 Ami fie INVENI'OI? y 1969 E. FAYMONVILLE 3,452,582

MULTISTAGE MACHINE TOOL Filed Jan. 5, 1967 Sheet 0 of s United StatesPatent 3,452,582 MULTISTAGE MACHINE TOOL Ernst Faymonville,Dusseldorf-Wersten, Germany, assignor to Malmedie & C0. MaschinenfabrikG.m.b.H. Filed Jan. 5, 1967, Ser. No. 607,547 Claims priority,application Germany, Mar. 16, 1966, M 68,783 Int. Cl. B21d 43/02, 45/00;B21j 11/00 U.S. Cl. 72-421 14 Claims ABSTRACT OF THE DISCLOSURE Amultistage press wherein the workpieces are transferred seriatim to aseries of successive stations and are ejected from female dies prior totransfer to the next station. In order to prevent uncontrolled travel ofWorkpieces in response to ejection, a back support is moved in front ofeach workpiece and intercepts it on ejection from the female die. Theback supports cooperate with the ejectors to maintain the workpieces inrequisite position for proper engagement by the transfer elements and,if the workpieces are hard to hold by the transfer elements alone, theback supports are installed in such a way that they travel with thetransfer elements and assist such elements in transferring theworkpieces from the preceding to the next-following stations.

Background of the invention The present invention relates to machinetools in general, and more particularly to improvements in automaticmultistage presses or analogous machines wherein relatively short andhard-to-grip workpieces are treated in a series of stages at a pluralityof successive working stations.

It is already known to treat ring-shaped, disk-shaped, circularplate-like or analogous workpieces whose axial length is but a fractionof their diameter in a series of stages at a plurality of successiveworking stations each of which accommodates a female die. The diescooperate with rams which are movable into and from deforming engagementwith workpieces, and the machine further comprises ejectors which expelpartly finished or finished workpieces from the respective dies. Atransfer mechanism whose holders grip ejected workpieces serves totransfer such workpieces from a preceding to the next-following workingstation. The holders of the transfer mechanism normally comprise pairsof gripping fingers or arms which are movable into and away fromengagement with workpieces. Such holders are satisfactory when theworkpieces are relatively long but are less reliable when the workpiecesresemble flat disks, rings or like relatively short bodies. Additionalproblems arise if such workpieces are actually propelled from the femaledies because the arms of the holders are often unable to intercept andto properly engage flying workpieces which resemble or comprise veryshort cones or rings. It happens frequently that, when an ejector isoperated to expel the workpiece from a female die, the disengagement ofthe workpiece from the die occurs abruptly and the thus disengagedworkpiece might move away from the ejector before it reaches thecorresponding holder. In multistage presses wherein the rams are movedin a vertical plane, a workpiece which is not properly grasped by theholder during transfer from a preceding to the next-following stationmight fall into the machine to cause complete breakdown of or lengthyinterruptions in operation. If the rams are reciprocated in a horizontalplane, workpieces which were permitted to fall are automaticallydiscarded as scrap.

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Accordingly, it is an important object of the present invention toprovide a multistage machine which is constructed and assembled in sucha way that the workpieces which are ejected from the tools at theworking stations are compelled to assume requisite positions forsatisfactory engagement by the elements of the transfer mechanism sothat the waste is reduced to a minimum and the workpieces cannot disturbthe operation of the machine.

Another object of the invention is to provide a multistage machinewherein the workpieces are prevented from performing uncontrolledmovements with reference to the ejectors and transfer mechanism even ifsuch workpieces are extremely flat, short, conical or otherwiseconfigurated in a way which renders them hard-tohold by the elements ofconventional transfer mechanisms.

A further object of the invention is to provide a machine wherein thetransfer mechanism is assisted in performing its intended function toinvariably prevent loss of workpieces during transfer from station tostation.

An additional object of the invention is to provide a multistage machinefor stepwise treatment of ring-shaped, disk-like, flat plate-like oranalogous articles wherein proper retention of such articles by thetransfer mechanism is guaranteed even if the articles tend to jumpsubsequent to ejection from the tools at the working stations.

A concomitant object of the invention is to provide a multistage machineof the above outlined character which can be utilized for shaping ofdifferent types of workpieces, wherein the movements of all parts can beautomatically controlled, wherein proper retention and interception ofejected workpieces does not interfere with forward or return strokes ofdeforming tools, and wherein the provision of means for interceptingejected workpieces contributes little, if anything, to bulkiness, floorspace requirements and/or weight of the machine.

Summary of the invention Briefly outlined, one feature of the presentinvention resides in the provision of a machine wherein workpieces aretreated in a series of stages at a plurality of successive equidistantworking stations, particularly to a multistage press for treatment ofworkpieces whose diameter exceeds their axial length (such as washers,rings, disks and like substantially flat bodies). In its elementaryform, the machine comprises a support which can constitute a componentpart of the machine frame, a series of work-supporting tools mounted onthe support, one at each of the working stations and each preferablyconstituting a female die, ejectors provided at the working stations andbeing operative to expel workpieces from the respective tools, transfermeans including a carriage and a plurality of work holders on thecarriage, the holders being movable into and from supporting engagementwith workpieces at the working stations and the carriage being movablewith reference to the support to transfer each workpiece which isengaged by a holder from registry with a tool at a preceding stationinto registry with a tool at the nextfollowing station, and a pluralityof back supports, one for each working station and each movable to andfrom an operative position in front of a workpiece in the respectivetool to intercept such workpiece on operation of the associated ejectorand to cooperate with such ejector to maintain the workpiece inrequisite position for engagement by a holder.

If the workpieces resemble short cones or similar hardto-hold articles,the back supports are preferably movable with the carriage of thetransfer means so as to remain in supporting engagement with workpiecesduring transfer from station to station.

The novel features which are considered as characteristic of theinvention are set forth in particular in the appended claims. Theimproved machine itself, however, both as to its construction and itsmode of operation, together with additional features and advantagesthereof, will be best understood upon perusal of the following detaileddescription of certain specific embodiments with reference to theaccompanying drawing.

Brief description of the drawing FIG. 1 is a fragmentary transversevertical section through one working station of a multistage press whichembodies the invention, the back supports being shown in retractedpositions and the workpieces being held between the male and femaletools upon completion of a deforming operation;

FIG. 2 illustrates the structure of FIG. 1 but with the back supportsshown in operative positions upon completed retraction of male tools;

FIG. 3 illustrates the structure of FIG. 2 but showing a workpiece in aposition it assumes on operation of the respective ejector when theworkpiece is held by such ejector and the associated back support;

FIG. 4 illustrates the structure of FIG. 3 but with a holder shown inactual engagement with a workpiece which is still held between theejector and the corresponding back support;

FIG. 5 illustrates the structure of FIG. 5 prior or subsequent totransfer of a workpiece from a preceding to the next following workingstation when the workpiece is engaged solely by the respective holderand is maintained in the path of the male tool; and

FIG. 6 is a fragmentary front elevational view of three adjoiningworking stations each of which accommodates a workpiece which is stillengaged by the corresponding holder.

Description of the preferred embodiments Referring first to FIG. 1,there is shown a multistage press which comprises a support 1 resemblinga platform and preferably forming part of the machine frame. The support1 carries a set of horizontal work-supporting tools 2 here shown asfemale dies which can cooperate with male tools or rams 7 to shapeworkpieces 13 in a series of successive operations each of which isperformed at a different working or treating station. FIG. 6 shows, byway of example, three equidistant working stations each of whichaccommodates a female die 2. The support 1 further carries a system ofadjustable links 3a which are pivotable on horizontal pins 3b andsupport an elongated horizontal guide rail 30 for a slide or carriage 3forming part of a transporting mechanism. The carriage 3 supports a rowof equidistant work-engaging holders 4, best shown in FIG. 6, each ofwhich comprises two crossed gripping arms or fingers movable into andaway from engagement with a workpiece 13 subsequent to ejection of suchworkpiece from its socket in the respective female die 2. Each workingstation further accommodates a reciprocable ejector 2a which isconstituted by the piston rod of a piston 2b which is installed in ahorizontal double-acting cylinder 20. The ejectors 2a are disposed in acommon horizontal plane and their forward ends can pass through centralopenings provided in the respective female dies 2 to eject theworkpieces 13 from their sockets in response to forward strokes of therespective pistons 2b. The conduits for supplying fluid to and forevacuating fluid from the cylinders 20 are not shown in the drawing.

The rams 7 are mounted on a slide or carriage 8 which is movable towardand away from the working stations so that the working ends of the ramsengage and deform the workpieces 13 when the slide 8 moves to the leftand assumes the position shown in FIG. 1. The drive mechanism whichreciprocates the slide 8 is of known design and its construction formsno part of the present invention. The same holds true for the drivewhich reciprocates the carriage 3 of the transporting mechanism, for thevalves which control the flow of fluid into and from the cylinders 20 ofthe ejectors 2a, and for the drive which is used to move a set of novelback supports 6 to and from operative positions shown in FIG. 2. Theseback supports 6 resemble short cylinders having portions or stems 6a ofreduced diameter which are reciprocable in horizontal bores providedtherefor in a vertical plate-like carrier 5. Each back support 6 isbiased toward the respective female die 2 (i.e., toward the exposed sideof a workpiece 13 which is supported by such female die) by a resilientelement which is shown in the form of a helical spring 14. The bias ofsprings 14 can be adjusted by nuts 6b which mesh with the stems 6a.

The carrier 5 is articulately connected with upper and lower links 11a,11 which are turnable on or with horizontal pivot pins 12a, 12 mountedon a lower carriage or slide 9. This carriage 9 is reciprocable along adovetailed guide rail 10 which is afiixed to or forms part of thesupport 1. The parts 5, 9, 11, 11a, 12, 12a together form a parallelmotion mechanism which can move the back supports 6 between theoperative positions of FIG. 2 and the retracted positions of FIG. 1. Theaxes of the back supports 6 remain parallel with the axes of theejectors 2a and each such ejector registers with one of the backsupports 6 when the carrier 5 is held in the operative position shown inFIG. 2. The springs 14 will yield and will store energy when theejectors 2a expel the workpieces 13 from the respective female dies 2whereby the spring-biased back supports 6 cooperate with the ejectors 2ato maintain the workpieces 13 in requisite optimum positions forengagement by the fingers or arms of the holders 4.

The mechanisms which feed blanks to the female die 2 at the first orforemost working station and the mechanisms which receive finishedworkpieces from the holder 4 that removes such finished workpieces fromthe female die 2 at the last working station are known in the art andare not shown in the drawing. Furthermore, the machine comprises asuitable programming unit which synchronizes movements of the slide 8with movements of the ejectors 2a, carriage 3 and links 11, 11a to carryout the operations in a desired sequence. The links 11, 11a areoscillated with or relative to their pivots 12, 12a to move the backsupports 6 to and from operative positions.

When moved to retracted positions (see FIG. 1), the ejectors 2a serve asstops to limit the forward strokes of the rams 7.

The operation is as follows:

FIG. 1 illustrates one of the rams 7 in its forward end position, i.e.,in a position corresponding to that upon completion of a working ordeforming stroke. The carrier 5 maintains the back supports 6 in theirretracted positions in which such back supports cannot interfere withforward and/or return strokes of the rams 7. The arms or fingers of theholders 4 are moved away from each other so that such arms are out ofthe way and cannot obstruct movements of the rams 7 and/or the ejectionof workpieces 13 from the respective female dies 2.

When the rams 7 are retracted (see FIG. 2), the pivots 12, 12a for thelinks 11, 11a are rotated in a counterclockwise direction to lift thecarrier 5 and to move the end faces of the back supports 6 against theexposed sides of the workpieces 13. In the next step which isillustrated in FIG. 3, the ejectors 2a are moved forwardly and expel theworkpieces 13 from the sockets of the female dies 2 whereby theworkpieces push the back supports 6 in a direction to the right, asviewed in FIG. 2, and to the positions shown in FIG. 3. Each workpiece13 is then clamped from opposite sides by one of the ejectors 2a and bythe corresponding back support 6. Thus, the axial length of theworkpieces 13 can be extremely small or very large without affecting theretaining action of the parts 2a, 6. This is particularly important whenthe workpieces 13 are flat disks or rings or very short cones which arehard to hold by the arms of the holders 4.

The next step is illustrated in FIG. 4. The holders 4 have moved theirarms into actual engagement with the adjoining workpieces 13, but suchworkpieces are still clamped between the ejectors 2a and thecorresponding back supports 6. Thus, no workpiece is released prior toproper engagement and retention by one of the holders 4. In thenext-following step (see FIG. 5 or 6), the pivots 12, 12a return theback supports 6 to their retracted positions and the pistons 2b retracttheir ejectors 211 so that the workpieces 13 are supported solely by thearms of the respective holders 4. The carriage 3 is then shifted alongthe upper guide rail 30 to move the workpieces 13 from registry with thefemale dies 2 at the preceding working stations into registry with thefemale dies at the nextfollowing working stations. The ejectors 2c aremoved forwardly to an extent necessary to determine the length offorward strokes of the rams 7, and the rams are moved forwardly to pressthe workpieces against the respective female dies 2. The arms of theholders 4 are disengaged from the workpieces as soon as such workpiecesare safely held between the female dies and the rams. The next workingcycle is then carried out in a manner as described above.

The last holder 4 can deliver finished workpieces to a chute or toanother receiving device for transfer of finished workpieces to storageor to a further machine. The female die 2 at the first or foremostworking station will receive a blank during intervals when the holders 4transfer workpieces from preceding to the next-following stations.

If the nature of workpieces 13 is such that they cannot be properlyretained by the arms of the holders 4, the carriage 9 for the carrier 5is reciprocated with the carriage 3 for the holders 4 and the backsupports 6 remain in operative positions until the workpieces 13 arebrought into registry with the female dies 2 at the next-followingworking stations. Thus, the back supports 6 can cooperate first with theejectors 2a to clamp the workpieces 13 on ejection from the female dies2, and such back supports can thereupon cooperate with the holders 4 toassist the holders in transferring workpieces from station to stationThe carriages 3 and 9 will be reciprocated in syn chronism if theworkpieces 13 resemble short cones or if such portions of the workpieceswhich are engaged by the holders 4 resemble short cones. A short cone islikely to slip out of the arms of a holder 4 but, when simultaneouslyengaged by a back support 6, it can be safely transferred from stationto station.

The machine may comprise two, three, four or more working stations,depending on the desired number of treatments to which a blank must besubjected in order to assume a desired size and/or shape.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featureswhich fairly constitute essential characteristics of the generic andspecific aspects of my contribution to the art.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended claims.

I claim:

1. A machine wherein workpieces are treated in a series of stages at aplurality of successive working stations, comprising a support;work-supporting tools mounted on said support at each of said stations;a plurality of movable ejectors provided at said stations, each of saidejectors engaging one of said workpieces for moving the same from itstool-engaging position into a transfer position; transfer meansincluding a carriage and a plurality of work holders on said carriage,said holders being movable into and from supporting engagement withworkpieces at said stations when the same are in said transfer positionsthereof and said carriage being movable with reference to said supportto transfer each workpiece which is engaged by a holder from saidtransfer position at one station into the transfer position at the nextfollowing station; means for moving said movable ejectors so that thesame move each of said workpieces engaged by the same from theirtool-engaging positions into their transfer positions; and a pluralityof back supports, each of said back supports adapted to engage acorresponding workpiece in its tool-engaging position and move togetherwith the same while said workpiece is moved into said transfer positionby movement of the corresponding ejector so that each workpiece is fullysupported and held by an ejector and the corresponding back supportduring movement of the workpiece from its tool-engaging position intoits transfer position in which latter position it is then engaged by aholder for transfer to the next following station.

2. A machine as defined in claim 1, particularly a multi-stage press forshaping of workpieces whose diameter exceeds the axial length thereof,wherein each of said tools is constituted by a female die and whereineach of said ejectors is reciprocable with reference to the respectivedie.

3. A machine as defined in claim 2, wherein each of said back supportsis reciprocable in parallelism with said ejectors and registers with oneof said ejectors in the operative position thereof, and furthercomprising resilient means for biasing said back supports aginst theworkpieces in a direction toward the respective ejectors.

4. A machine as defined in claim 3, further comprising carrier means formoving said back supports to and from operative positions.

5. A machine as defined in claim 4, further comprising link meanspivotable about predetermined axes and articulately coupled to saidcarrier means to effect movement of back supports to and from saidoperative positions.

6. A machine as defined in claim 4, wherein said carrier means isprovided with a plurality of parallel bores and each of said backsupports comprises a portion which is reciprocable in one of said bores,said resilient means comprising springs operating between said carriermeans and said back supports to urge such back supports toward thecorresponding ejectors, said back supports being arranged to yield toworkpieces and to deform said springs in response to operation of therespective ejectors.

7. A machine as defined in claim 1, further comprising a second carriagefor said back supports, said second carriage being movable with saidfirst mentioned carriage so that the back supports can remain inengagement with workpieces during transfer between successive stations.

8. A machine as defined in claim 7, wherein said support comprisesparallel guide means for said carriages and wherein each of saidcarriages is reciprocable along the respective guide means throughdistances corresponding to those between said tools.

9. A machine as defined in claim 1, wherein said ejectors arereciprocable in a common horizontal plane and said carriage isreciprocable in a horizontal path at a level above and at right anglesto said ejectors, said back supports being movable upwardly and axiallyof said tools to said operative positions.

10. A machine as defined in claim 1, further comprising second toolsreciprocable into and away from deforming engagement with workpiecescarried by said first mentioned tools when the back supports are movedaway from said operative positions.

11. A machine as defined in claim 1, further comprising resilient meansfor biasing said back supports against the workpieces and toward therespective ejectors and means for adjusting the bias of said resilientmeans.

12. A machine as defined in claim 1, wherein said holders have grippingarms which are movable with reference to each other and wherein thework-pieces resemble substantially flat bodies.

13. A machine as defined in claim 1, wherein said ing a parallel motionmechanism for moving said back 5 supports to and from operativepositions.

References Cited UNITED STATES PATENTS 2,687,660 2,721,343 10/1955Friedman 10--12 8/1954 Friedman 72-346 10 8 3,120,770 2/1964 Hoyt 10-123,274,626 9/ 1966 Van de Mecrendonk 10-12 FOREIGN PATENTS 1,107,4895/1961 Germany.

CHARLES W. LANHAM, Primary Examiner.

E. M. COMBS, Assistant Examiner.

US. Cl. X.R.

